This chapter is from the book

This chapter is from the book

Overview of VPNs and VPN Technologies

Cisco products support the latest in VPN technology. A VPN is a service that
offers secure, reliable connectivity over a shared public network infrastructure
such as the Internet.

Figure 1-1 shows
various VPNs between a main site and branch offices and small office, home office
(SOHO) workers.

VPNs maintain the same security and management policies as a private network.
They are the most cost effective method of establishing a virtual point-to-point
connection between remote users and an enterprise customer's network. There
are three main types of VPNs.

Intranet VPNsLink enterprise customer headquarters, remote
offices, and branch offices to an internal network over a shared infrastructure
using dedicated connections. Intranet VPNs differ from extranet VPNs in that
they allow access only to the enterprise customer's employees.

Extranet VPNsLink outside customers, suppliers, partners, or
communities of interest to an enterprise customer's network over a shared
infrastructure using dedicated connections. Extranet VPNs differ from intranet
VPNs in that they allow access to users outside the enterprise.